The doctor said jokingly that his own infection of the virus _______ the discovery of a vaccine (疫苗)of the disease.
Some people eat with their eyes.They prefer to order what ________ nice.
It was already past midnight and only three young men ________ in the tea house.
On hearing the news of the accident in the coal mine,she ________ pale.
The effect of the medicine on this kind of disease remains ________.
The card reads:“Dear Mom and Dad,they are ________ everyone write home.Love,Joey.”